Enhanced Cross Stream Mechanical Thrombectomy Catheter

ABSTRACT

An enhanced cross stream mechanical thrombectomy catheter with backloading manifold having a distal end with outflow and inflow orifices at one side for producing concentrated cross stream jet flow for selective and concentrated thrombus ablation during thrombectomy procedures. The invention provides for suitable distancing of high powered ablation or suction forces from the near walls of the vasculature. Cross stream flow emanating from the one side of the distal end of the catheter resultantly urges the distal end of the catheter and thus the opposing non-orif iced side of the distal end of the catheter toward and against the vascular wall to inhibit contact of the inflow orifice with the vascular wall. Features of the invention include a geometrically configured insert to facilitate the backloading or exchange of guidewires.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No.12/174,978, filed Jul. 17, 2008, now U.S. Pat. No. 8,162,877, issuedApr. 24, 2012, which is a divisional of U.S. application Ser. No.11/009,720, filed on Dec. 10, 2004, which is abandoned, the contents ofwhich are incorporated herein by reference. This application is relatedto U.S. application Ser. No. 10/455,096 filed Jun. 5, 2003, now U.S.Pat. No. 7,226,433, issued Jun. 5, 2007.

BACKGROUND OF THE INVENTION

The present invention is for a thrombectomy catheter, and moreparticularly, relates to an enhanced cross stream mechanicalthrombectomy catheter which accommodates interchanging of guidewiresthrough rear loading of a guidewire, as well as loading of a guidewirein a conventional manner, and also provides for improved cross streamablation at a thrombus site. The intended use of this invention is forthe detachment and removal of unwanted tissues, such as thrombus, fromwithin biological conduits.

DESCRIPTION OF THE PRIOR ART

In current cross stream catheters, vessel damage by the multipleinflow/outflow cross stream catheters involves the vessel wall beingsucked into the catheter at the side inlet orifice of the catheter. Thehigh velocity fluid jets nick the vessel that is sucked into thecatheter side inflow orifice. With the design described by the presentinvention, the vessel is pushed away by a single side outflow. The sideof the catheter with no orifices is pushed against the vessel andconsequently no damage results. This new mechanical thrombectomy designis referred to as the Enhanced Cross Stream Mechanical ThrombectomyCatheter with Backloading Manifold. The design employs one set of inflowand outflow orifices instead of the symmetrical multiple orificeconfiguration. Generally speaking, the cross sectional area of multiplesets of outflow/inflow orifices of prior art devices are newly combinedinto one set having a larger but equal cross sectional outflow/infloworifice area to substantially increase and concentrate the cross streamaction on one side of the device, thereby increasing the localized flowintensity considerably. In the present invention, all the flow isconcentrated to one set of orifices and, in addition, the area forrecirculation is maximized since it is designed to have a guidewireremoved or pulled back out of the flow zone while using the device.Removing the guidewire from the orifice area of the catheter removes asubstantial fluid restriction between the single side inflow orifice andthe single side outflow orifice. In theory, removing this fluidrestriction in all cross stream catheter designs should increasecatheter performance. However, in the multiple orifice pair arrangementsof the prior art, internal turbulent eddies consumed the area and anincrease in performance often did not accompany the retraction of theguidewire. The single inflow orifice and outflow orifice arrangement ofthe present invention simplifies the internal fluid pathway, and as aresult, marked flow increase associated with guidewire removal isconsistent and dramatic. The guidewire does not need to be pulled outcompletely to achieve substantial improvements in efficacy. In fact,even with the guidewire in place, it is much more effective thansimilarly sized cross stream thrombectomy catheters. Furthermore,retracting the guidewire to free the orifice area of the catheterresults in an even greater increase in catheter performance. Thisremoval of the guidewire from the region of cross stream action (i.e.,from the ID of the catheter) greatly increases the flow volume andreduces flow resistance in which recirculation can more readily occur,thereby enhancing function. Furthermore, in existing designs, aguidewire cannot be reliably retracted from the catheter without thepotential of the guidewire exiting the inflow orifices when thephysician pushes it back through the tip of the device. The orifices ofexisting designs can be made smaller, but then a greater number oforifices must be provided to maintain suitable flow, resulting inlimiting cross stream action since the resistance though smallerorifices is greater. Therefore, a new arrangement was created to solvethe problem. Specifically, the high pressure tube is placed in thecenter of the large inflow and outflow orifice effectively creating twosmaller orifices with the least amount of resistance to flow withminimized manufacturing cost. The high pressure tube further directs theguidewire up and out of the tip of the distal portion of the catheterdue to its geometry (i.e., rounded surface, thickness keeps wire awayfrom wall, etc.). In summary, by utilizing one set of large inflow andoutflow orifices with the ability to remove and replace the guidewirewhen desired, the cross stream ablation action can be concentrated andenhanced. Furthermore, the ability of removing and replacing theguidewire at the flexible tip or at the proximal end of the manifoldleads to further enhancement. The user may replace the same guidewire ormay utilize another guidewire of his choice (“guidewire swapping”). Thisability is favorable to physicians since they want as many choices toperform their job to the best of their ability as possible (i.e.,beneficial so they do not lose wire position, or that they may want astiffer or more floppy guidewire to cross a tight stenosis or traversetortuous anatomy). This enhancement is achieved through simple changesto the manifold, whereby an insert is included for guidewire routing.

There is yet another benefit to the asymmetrical design of the presentinvention at the catheter distal end where all of the jet stream outflowis directed from one side of the catheter distal end resulting in apowerful concentration of directed force and increased flow caused byremoval or proximal retardation of the guidewire. Such benefit resultsin the distal portion of the catheter reactingly being directed andforced against the vessel wall opposite to the cross stream action. Thismovement beneficially keeps the inflow and outflow orifices away fromthe vessel wall. It has been shown that vessel contact with the inflowor outflow orifices (interior jets, suction, or a combination of both)can cause vessel damage in various degrees. Therefore, this “nakedcatheter” (i.e., there are other designs having cages or balloons whichwould keep the jet flow from contacting the walls, but this design usesactive jet flow to position the device) design is very safe with respectto vessel wall damage.

Some alternatives of this design would use differently shaped orifices,such as slots, instead of holes, etc. Round, oval, elliptical, obround,tapered, slotted, rectangular, triangular, rounded corner, protruding,or multiple-radius configurations can be utilized for the inflow and/oroutflow orifices, where the orifices could be shaped such as to directthe flow in a preferred direction.

The catheter body could also be shaped to maximize the effectiveness ofthe flow. Also, the body of the catheter at the distal end may include a180.degree. reversal where the reversed distal end is utilized to aid inremoving material from the vessel wall. The effectiveness of thecatheter could also be increased by increasing the flow to the cathetertip, which would impart more energy to the system to do work.

There is an alternative design that is similar in principle to the firstembodiments of the present invention but which uses a physical barrierto deflect the flow out the side outflow orifice. In the current crossstream designs, a static or slow moving column of fluid captures theenergy from the high velocity fluid jets resulting in a recoveredpressure near the side outflow orifices. This recovered pressure drivesfluid out the side outflow orifices. The general principle is that thevelocity fluid jets entrain surrounding fluid which enters the catheterfrom the side inlet orifices. This excess fluid must exit the cathetersince the outflow rate of the catheter is balanced to equal the infusedflow rate from a suction source, such as a pump. As a result, higherrecovered pressure near the side outflow orifices, which generates therecirculating flow pattern at the catheter tip, is seen. There are anumber of fluid mechanical inefficiencies associated with such a design.Primarily, the strong high velocity fluid jets end up traveling downpast the side outflow orifices and eventually break up into largeturbulent eddies. Guiding the flow out a side outflow orifice canpreserve some of this energy rather than having it consumed byturbulence inside the catheter. Another alternative design isincorporated to implement waste flow removal by orienting most of thehigh velocity fluid jets forward and then deflecting them out the distalend of the catheter where a small number of proximal-facing highvelocity fluid jets are utilized to drive outflow from the catheter. Theother alternative is to apply a roller pump driven waste line to theguide catheter itself and use the roller pump negative pressure toevacuate the waste flow while the deflecting catheter is infusing flowinto the patient.

SUMMARY OF THE INVENTION

The general purpose of the present invention is to provide an enhancedcross stream mechanical thrombectomy catheter with backloading manifold.The enhanced cross stream mechanical thrombectomy catheter withbackloading manifold is capable of traditional loading over the proximalend of a guidewire or accommodational backloading of the distal end of aguidewire, such as would be useful during an exchange of guidewireswhether during or prior to a thrombectomy procedure. Loading of aguidewire through the proximal end of the backloading manifold isaccommodated and facilitated by a self-sealing arrangement including ahemostatic nut and a seal at the proximal end of the backloadingmanifold and by a tubular insert centrally located along the interior ofthe tubular central body of the backloading manifold. The insertincludes a proximally-facing beveled surface entrance leading to anintegral and distally located central passageway which extends along thegreater portion of the length of the insert where such proximally-facingbeveled surface entrance is useful for directing and loading a guidewire(i.e., a proximally loaded and distally directed guidewire) which isfirst directed in a central direction by the proximally-facing beveledsurface entrance followed by passage through the central passageway. Thedistal and truncated portion of the insert central passageway connectsto the proximal end of a catheter tube composed of a braided cathetertube successively connected to a plastic smooth catheter tube leading toan integral flexible and tapered distal tip at the distal portion of thesmooth catheter tube. The geometry of a fluid jet emanator and relatedstructure near the distal tip of the smooth catheter tube assists andpromotes passage of a guidewire passing in either direction through thefluid jet emanator and related structure.

Cross stream flow at the distal portion of the smooth catheter tube asproduced by a fluid jet emanator is enhanced by the use of one outfloworifice and one inflow orifice, thereby allowing concentration andintensity of the cross stream flow to provide only one localized regionof thrombus ablation. Such ablation flow creates forces urging thedistal portion of the plastic catheter tube away from the ablation area(i.e., away from the cross stream flow) in order that the vascular wallsare not blockingly engaged by the inflow orifice. Such distancing isalso helpful in keeping the cross stream flow from being dangerouslyclose to the vascular wall, thereby minimizing the possibility ofvascular wall damage.

According to one or more embodiments of the present invention, there isprovided an enhanced cross stream mechanical thrombectomy catheter withbackloading manifold, including a backloading manifold having an exhaustbranch and a high pressure connection branch extending from a tubularcentral body of the backloading manifold, a hemostatic nut threadinglysecured to the proximal portion of a proximal cavity body of thebackloading manifold, a tubular insert located in an insert cavity ofthe backloading manifold, a strain relief extending distally from adistal manifold extension of the backloading manifold, a catheter tubeformed in part of a braided catheter tube being connected to the insertand extending through the strain relief and in part of a plastic smoothcatheter tube successively connected to the braided catheter tube, aninflow and an outflow orifice spaced longitudinally along one side ofand located near the proximal end of the plastic smooth catheter tube,an integral flexible tip at the distal end of the plastic smoothcatheter tube, and a high pressure tube extending through the highpressure connection branch, through portions of the backloadingmanifold, partially through the insert, and through the catheter tubecomposed of the braided catheter tube and plastic smooth catheter tubeto terminate as a fluid jet emanator near the distal portion of theplastic smooth catheter tube where such termination is distal of theinflow and the outflow orifices, as well as other components describedherein.

One significant aspect and feature of the present invention includes anenhanced cross stream mechanical thrombectomy catheter with backloadingmanifold with enhanced efficacy due to concentration of all the flow toone set of inflow and outflow orifices with a guidewire in place.

Another significant aspect and feature of the present invention includesan enhanced cross stream mechanical thrombectomy catheter withbackloading manifold with even greater enhanced efficacy due toconcentration of all the flow to one set of inflow and outflow orificeswith the removal, retarding or other positioning of a guidewire.

Yet another significant aspect and feature of the present inventionincludes an enhanced cross stream mechanical thrombectomy catheter withbackloading manifold that utilizes the position of the high pressuretube in relation to the outflow and inflow orifices to enable aguidewire to move freely in and out of the catheter tube without goingout one of the orifices.

Still another significant aspect and feature of the present inventionincludes an enhanced cross stream mechanical thrombectomy catheter withbackloading manifold that has a specially designed insert that allows aguidewire to be completely removed and replaced or exchanged for anotherdesired guidewire.

Another significant aspect and feature of the present invention includesan enhanced cross stream mechanical thrombectomy catheter withbackloading manifold that can be safer than other cross stream designssince the outflow orifice flow pushes the distal catheter end containingthe inflow orifice and the outflow orifice away from the vessel wall(the region were damage can occur), thereby minimizing the possibilityof blood vessel wall ingestion by the inflow orifice.

Another significant aspect and feature of the present invention includesan enhanced cross stream mechanical thrombectomy catheter withbackloading manifold that employs many of the above significant aspectsand features plus additionally including a catheter having a reverseddistal end incorporated to intimately contact and remove grumousmaterial from a vessel wall by direct abrading contact and by crossstream flow ablation.

Another significant aspect and feature of the present invention includesan enhanced cross stream mechanical thrombectomy catheter withbackloading manifold that employs many of the above significant aspectsand features and has inflow and outflow orifices shaped or sized to giveoptimal flow direction or performance.

Another significant aspect and feature of the present invention includesan enhanced cross stream mechanical thrombectomy catheter withbackloading manifold that employs many of the above significant aspectsand features and wherein the efficacy can be increased by increasingflow to the jet orifices (i.e., currently 60 cc of fluid delivered perminute . . . increased to 100 cc/min).

Another significant aspect and feature of the present invention includesan enhanced cross stream mechanical thrombectomy catheter withbackloading manifold that employs deflection for concentrating andredirecting high velocity fluid jets to form cross stream jets with orwithout exhaust as an alternative design.

Another significant aspect and feature of the present invention includesan enhanced cross stream mechanical thrombectomy catheter withbackloading manifold that can operate in a pressure range of 100 to20,000 psi.

Yet another significant aspect and feature of the present invention isthe use of additional outflow orifices and inflow orifices in angularoff-center opposition to the main outflow orifice and the infloworifice.

Having thus described embodiments of the present invention and set forthsignificant aspects and features of the present invention, it is theprincipal object of the present invention to provide an enhanced crossstream mechanical thrombectomy catheter with backloading manifold.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects of the present invention and many of the attendantadvantages of the present invention will be readily appreciated as thesame becomes better understood by reference to the following detaileddescription when considered in connection with the accompanyingdrawings, in which like reference numerals designate like partsthroughout the figures thereof and wherein:

FIG. 1 is an isometric view of an enhanced cross stream mechanicalthrombectomy catheter with backloading manifold, the present invention;

FIG. 2 is an isometric exploded view of the enhanced cross streammechanical thrombectomy catheter with backloading manifold;

FIG. 3 is an exploded cross section side view of the components of theenhanced cross stream mechanical thrombectomy catheter with backloadingmanifold;

FIG. 4 is an isometric view of the insert showing an elongated slotextending through the main body;

FIG. 5 is a cross section view of the assembled elements of FIG. 3;

FIG. 6 is a cross section view of the enhanced cross stream mechanicalthrombectomy catheter with backloading manifold along line 6-6 of FIG.5;

FIG. 7 is a bottom view of the distal end of the enhanced cross streammechanical thrombectomy catheter with backloading manifold showing thesmooth catheter tube, the outflow orifice, and the inflow orifice, aswell as the high pressure tube visible through the outflow orifice andthe inflow orifice;

FIG. 8 is an isometric view of the fluid jet emanator;

FIG. 9 is a side view in cross section along line 9-9 of FIG. 8 of thefluid jet emanator;

FIG. 10 is a side view in cross section illustrating the elements ofFIG. 9 secured in the distal portion of the smooth catheter tube by aradiopaque marker band, as well as showing the cross stream flow;

FIG. 11 is a side view of the distal region of the enhanced cross streammechanical thrombectomy catheter with backloading manifold showing thedistal end of a smooth catheter tube assembly positioned in a bloodvessel (shown in cross section) at a site of a thrombotic deposit orlesion;

FIG. 12 is a side view in cross section illustrating the introduction ofa guidewire into the enhanced cross stream mechanical thrombectomycatheter with backloading manifold;

FIG. 13, a first alternative embodiment, is an isometric view of anenhanced cross stream mechanical thrombectomy catheter with backloadingmanifold;

FIG. 14 is a partially exploded isometric view of the enhanced crossstream mechanical thrombectomy catheter with backloading manifoldillustrated in FIG. 13;

FIG. 15 is a cross section side view of the components of the distalregion of the smooth catheter tube assembly along line 15-15 of FIG. 13;

FIG. 16 is a magnified cross section view along line 16-16 of FIG. 15;

FIG. 17 is a cross section view of the smooth catheter tube assemblyalong line 17-17 of FIG. 16;

FIG. 18 illustrates the distal portion of the smooth catheter tubeassembly of the first alternative embodiment in cross section;

FIG. 19 is a side view of the distal region of the enhanced cross streammechanical thrombectomy catheter with backloading manifold constitutingthe first alternative embodiment showing the distal end of the smoothcatheter tube assembly positioned in a blood vessel (shown in crosssection) at a site of a thrombotic deposit or lesion;

FIG. 20, a second alternative embodiment, is an isometric view of anenhanced cross stream mechanical thrombectomy catheter with backloadingmanifold;

FIG. 21 is a partially exploded isometric view of the enhanced crossstream mechanical thrombectomy catheter with backloading manifoldillustrated in FIG. 20;

FIG. 22 is a cross section side view of the components of the distalregion of the smooth catheter tube assembly along line 22-22 of FIG. 20;

FIG. 23 is a magnified cross section view along line 23-23 of FIG. 22;

FIG. 24 is a cross section view of the smooth catheter tube assemblyalong line 24-24 of FIG. 23;

FIG. 25 illustrates the distal portion of the smooth catheter tubeassembly of the second alternative embodiment in cross section;

FIG. 26 is a side view of the distal region of the enhanced cross streammechanical thrombectomy catheter with backloading manifold constitutingthe second alternative embodiment showing the distal end of the smoothcatheter tube assembly positioned in a blood vessel (shown in crosssection) at a site of a thrombotic deposit or lesion;

FIG. 27, a third alternative embodiment, is an isometric view of anenhanced cross stream mechanical thrombectomy catheter with backloadingmanifold including a smooth catheter tube which is curved;

FIG. 28 is a partially exploded isometric view of the enhanced crossstream mechanical thrombectomy catheter with backloading manifoldillustrated in FIG. 27;

FIG. 29 is a cross section side view of the components of the distalregion of the smooth catheter tube assembly along line 29-29 of FIG. 27;

FIG. 30 is a side view of the distal region of the enhanced cross streammechanical thrombectomy catheter with backloading manifold constitutingthe third alternative embodiment at a thrombus site;

FIG. 31 is a cross section view along line 31-31 of FIG. 30;

FIG. 32, a fourth alternative embodiment, is a side view of a smoothcatheter tube having an alternate shape outflow orifice;

FIG. 33, a fifth alternative embodiment, is a view of the distal portionof an alternatively provided smooth catheter tube assembly incorporatingthe components of the smooth catheter tube assembly shown in the firstembodiment and including additional outflow orifices and inflow orificesin angular off-center opposition to the main outflow orifice and themain inflow orifice;

FIGS. 34 a and 34 b are cross section views through the outflow orificesand inflow orifices of the smooth catheter tube assembly along lines 34a-34 a and 34 b-34 b of FIG. 33 showing cross stream jet flow regions;

FIG. 35 is a side view in cross section like FIG. 10 wherein the distalportion of the smooth catheter tube additionally includes an outfloworifice and an inflow orifice; and,

FIG. 36 is a side view of the distal region of the enhanced cross streammechanical thrombectomy catheter with backloading manifold constitutingthe fifth alternative embodiment showing the distal end of the smoothcatheter tube assembly positioned in a blood vessel shown in crosssection at a site of a thrombotic deposit or lesion.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 is an isometric view of an enhanced cross stream mechanicalthrombectomy catheter with backloading manifold 10, the presentinvention. Externally visible major components of the invention includea centrally located backloading manifold 12, a hemostatic nut 14threadingly secured to the backloading manifold 12, an introducer 15, aflexible and tapered strain relief 16 connected to and extending fromthe backloading manifold 12, a catheter tube composed of a braidedcatheter tube 18 of flexible or semi-flexible material, preferablypolyimide or other such suitable composition, connected to thebackloading manifold 12 and extending through the tapered and flexiblestrain relief 16 and a smooth catheter tube assembly 19 having a smoothcatheter tube 20 of plastic composition connected to and extendingdistally from the braided catheter tube 18, and an outflow orifice 22and an inflow orifice 24 located in longitudinal alignment along animaginary line at the distal portion of the smooth catheter tube 20 neara flexible tapered tip 26 located distally at the end of the smoothcatheter tube 20. The components of the smooth catheter tube assembly 19are depicted fully in FIGS. 2 and 3. For illustration purposes, theoutflow orifice 22 and the inflow orifice 24, which extend through thesmooth catheter tube 20, are shown on the side of the smooth cathetertube 20, but can be located along any imaginary line extendinglongitudinally along a distal surface of the smooth catheter tube 20,such as is shown in FIGS. 3, 7, 10 and 11. Normally, the catheter tube18 is formed as a braided construction for strength, as shown, but itcan be effectively formed in other ways: for example, by usingreinforcing components such as fibers, wound strands, rings, wraps, orcombinations thereof. Other externally visible major components of theinvention include a radiopaque marker band 28 located on the smoothcatheter tube 20 in close proximity to and proximal to the outfloworifice 22, a radiopaque marker band 30 located on the smooth cathetertube 20 in close proximity to and distal to the inflow orifice 24, ahigh pressure connection branch 32 extending from the central body 34 ofthe backloading manifold 12, an exhaust branch 36 extending from thejunction of the central body 34 of the backloading manifold 12 and thehigh pressure connection branch 32, and a high pressure connector 64engaging with and extending from the high pressure connection branch 32of the backloading manifold 12. An orifice 65 located in the highpressure connection branch 32 allows for the introduction of adhesive 61(FIG. 5) to secure the high pressure connector 64 in the high pressureconnection branch 32.

FIG. 2 is an isometric exploded view of the enhanced cross streammechanical thrombectomy catheter with backloading manifold 10, thepresent invention, and FIG. 3 is an exploded cross section side view ofthe components of the enhanced cross stream mechanical thrombectomycatheter with backloading manifold 10. With reference to FIGS. 2 and 3,the present invention is now further described.

The backloading manifold 12 includes the central body 34 which istubular and has on one end a proximally located cavity body 38 includingan externally located threaded surface 40 and on the other end adistally located tubular manifold extension 42, including an orifice 41which is utilized to introduce adhesive 43 (FIG. 5) to secure theproximal end of the braided catheter tube 18 to the distal manifoldcavity 56. A multi-radius insert cavity 44 is continuously co-locatedwithin the central body 34 and a portion of the adjacent cavity body 38.The multi-radius insert cavity 44 is comprised of an elongated distalinsert cavity portion 46 located coaxially within the central body 34adjacent to and connecting to a proximal insert cavity portion 48located coaxial to the cavity body 38 in continuous fashion. The insertcavity 44 accommodates an insert 50. A proximal manifold cavity 52 islocated coaxially within the cavity body 38 and is continuous with andproximal to the proximal insert cavity portion 48 and an annular cavitywall 54 and an annular and planar surface 55 located between the annularcavity wall 54 and the proximal insert cavity portion 48. The manifoldextension 42 extending distally from the distal end of the backloadingmanifold 12 includes an inwardly located distal manifold cavity 56 forpassage of the proximal end of the braided catheter tube 18. Theexterior of the manifold extension 42 accommodates the strain relief 16.The strain relief 16 is of flexible construction and includes aproximally located strain relief mounting cavity 58 connected to apassageway 60 both of which extend along the longitudinal axis of thestrain relief 16. The strain relief mounting cavity 58 accommodates themanifold extension 42, which can be appropriately secured therein, suchas by adhesive or mechanical interference. The high pressure connectionbranch 32 includes a high pressure connection branch passageway 62intersecting and communicating with the distal insert cavity portion 46of the insert cavity 44, as well as offering accommodation of thethreaded high pressure connector 64. A ferrule 66 having a central bore70 is accommodated by the lumen 67 of the high pressure connector 64.One end of a high pressure tube 71 is accommodated by and sealinglysecured to the central bore 70 of the ferrule 66, such as by a weldmentor mechanical interference. An exhaust branch passageway 72 central tothe exhaust branch 36 communicates with the high pressure connectionbranch passageway 62 and with the distal insert cavity portion 46 of theinsert cavity 44. The exhaust branch 36 has a threaded surface 63 at itsend for attaching to suction apparatus. The entire insert 50 isaccommodated by the insert cavity 44 where the distal insert cavityportion 46 and the proximal insert cavity portion 48 fittinglyaccommodate separate geometric configurations of the insert 50.

As also shown in the isometric view of FIG. 4, the insert 50 includes atubular main body 74 having a proximally located shoulder 76 which canbe tapered or of other suitable geometric configuration. The shoulder 76engages an annular transition stop surface 78 (FIG. 3) between theproximal insert cavity portion 48 and the distal insert cavity portion46. One end of a central passageway 80 truncatingly intersects anelongated slot 82; and such central passageway also intersects a bore 84which is also truncated by intersecting the elongated slot 82, i.e., thecentral passageway 80 adjoins bore 84 and each is truncated byintersection with the elongated slot 82. The elongated slot 82 extendsthrough the main body 74 to intersect and align to a portion of thelongitudinal axis of the insert 50. The elongated slot 82 accommodatespassage of the high pressure tube 71, as shown in FIG. 5. The centralpassageway 80 has a proximally located beveled surface entrance 86resembling a cone. The beveled surface entrance 86 is utilized forguidance and alignment for backloading of a guidewire through thebackloading manifold 12, as later described in detail.

Beneficial to the instant invention is the use of a self-sealinghemostatic valve 88, flanking washers 90 and 92, and an introducer 15which are related to a patent application entitled “ThrombectomyCatheter Device Having a Self-Sealing Hemostatic Valve,” U.S. Pat. No.7,226,433. The self-sealing hemostatic valve 88, which is slightlyoversized with respect to the proximal manifold cavity 52, and thewashers 90 and 92 are aligned in and housed in the proximal manifoldcavity 52 at one end of the backloading manifold 12. The hemostatic nut14 includes a centrally located cylindrical boss 94, a centralpassageway 96 having a beveled surface entrance 97 extending through andin part forming the cylindrical boss 94, and internal threads 98. Theinternal threads 98 of the hemostatic nut 14 can be made to engage thethreaded surface 40 of the backloading manifold 12, whereby thecylindrical boss 94 is brought to bear against the washer 90 toresultantly bring pressure to bear as required against the self-sealinghemostatic valve 88 and washer 92. The washers 90 and 92 and theself-sealing hemostatic valve 88 are captured in the proximal manifoldcavity 52 by threaded engagement of the hemostatic nut 14 to the cavitybody 38 of the backloading manifold 12. Also included in the hemostaticnut 14 is an annular lip 100 which can be utilized for snap engagementof particular styles or types of introducers, as required, such asintroducer 15 provided to aid in accommodation of a guidewire in eitherdirection and to provide for venting for the interior of the backloadingmanifold 12. The introducer 15 includes a centrally located shaft 102with a central passageway 103 having a beveled surface entrance 105, anactuating handle 104, and rings 106 and 108 about the shaft 102. Alsoshown in FIG. 3 is a lumen 110 central to the braided catheter tube 18which joiningly connects to and communicates with a lumen 112 central tothe smooth catheter tube 20. A circular support ring 114 is suitablyattached to the high pressure tube 71, such as by a weldment, and islocated within the smooth catheter tube 20 in supporting alignment withthe radiopaque marker band 28. A fluid jet emanator 116 includingterminated loop 117 at the distal end of the high pressure tube 71 and acircular support ring 124 is located distal of the inflow orifice 24within the distal end of the smooth catheter tube 20 in alignment withthe radiopaque marker band 30, as later shown in detail in FIG. 10. Thecircular support rings 114 and 124 together with the respectiveassociated radiopaque marker bands 28 and 30 constitute means forretaining the high pressure tube 71 in alignment with the catheter tubecomposed of braided catheter tube 18 and the smooth catheter tube 20.

FIG. 4 is an isometric view of the insert 50 showing the elongated slot82 extending through the main body 74 in intersection with the centralpassageway 80 and the bore 84. The elongated slot 82 is beneficial foraccommodation of the high pressure tube 71, as well as for communicationbetween the combined lumens 110 and 112 of the braided catheter tube 18and the smooth catheter tube 20, respectively, and the high pressureconnection branch passageway 62 and the exhaust branch passageway 72, asshown in FIG. 5.

FIG. 5 is a cross section view of the assembled elements of FIG. 3.Particularly shown is the relationship of the high pressure tube 71, theinsert 50, the lumen 110 of the braided catheter tube 18, and theproximal end of the braided catheter tube 18. The proximal portion ofthe high pressure tube 71 extends distally from the ferrule 66 throughthe high pressure connection branch passageway 62, through the elongatedslot 82 of the insert 50 while traversing the distal portion of thecentral passageway 80 en route to and into the lumen 110 of the braidedcatheter tube 18, and thence along the lumen 110 and into the lumen 112of the smooth catheter tube 20 to terminate as part of the fluid jetemanator 116 shown adjacent to the flexible tapered tip 26 at the distalend of the smooth catheter tube 20. In addition to providing a passagefor the high pressure tube 71, the elongated slot 82 allowscommunication between the lumen 110 of the braided catheter tube 18 andthe lumen 112 of the smooth catheter tube 20, collectively, and the highpressure connection branch passageway 62 and the exhaust branchpassageway 72 for evacuation of effluence therefrom. Also shown is thejunction 118 between the smooth catheter tube 20 and the braidedcatheter tube 18, such junction being suitably effected to provide for asmooth and continuous coupling of the smooth catheter tube 20 and thebraided catheter tube 18.

FIG. 6 is a cross section view of the enhanced cross stream mechanicalthrombectomy catheter with backloading manifold 10 along line 6-6 ofFIG. 5. Shown in particular is the elongated slot 82 through which thehigh pressure tube 71 passes (passage of high pressure tube 71 notshown) and through which communication takes place between the lumen 110of the braided catheter tube 18 and the high pressure connection branchpassageway 62 and the exhaust branch passageway 72. Also shown is alumen 120 central to the high pressure tube 71.

FIG. 7 is a bottom view of the distal end of the enhanced cross streammechanical thrombectomy catheter with backloading manifold 10 showingthe smooth catheter tube 20 and the outflow orifice 22 and the infloworifice 24, as well as the high pressure tube 71 visible through theoutflow orifice 22 and the inflow orifice 24.

FIG. 8 is an isometric view and FIG. 9 is a side view in cross sectionalong line 9-9 of FIG. 8 of the fluid jet emanator 116. The fluid jetemanator 116 includes a terminated loop 117 at the distal end of thehigh pressure tube 71 and includes the support ring 124. The terminatedloop 117 includes a plurality of proximally directed jet orifices 122a-122 n. The support ring 124 suitably secures to the distal surface ofthe terminated loop 117 such as by a weldment. A center void 126 of theterminated loop 117 allows for passage of a guidewire or other suitabledevices. The support ring 124, a tubular device, includes a centralpassageway 128 corresponding in use to that of the center void 126 ofthe terminated loop 117 for passage of a guidewire or other suitabledevices. A distally located annular shoulder 130 on the support ring 124allows for the inclusion of a beveled annular surface 132 juxtaposingthe central passageway 128 to aid in the guided accommodation of aguidewire or other suitable device at the distal portion of the centralpassageway 128. A wide annular groove 134 is formed between the annularshoulder 130 and the distally facing surface of the terminated loop 117and the smaller radiused body of the support ring 124. The wide annulargroove 134 is utilized to secure the fluid jet emanator 116 at asuitable location in the distal portion of the smooth catheter tube 20,as shown in FIG. 10.

Mode of Operation

The mode of operation of the enhanced cross stream mechanicalthrombectomy catheter with backloading manifold 10 is explained withreference to FIGS. 10, 11 and 12. FIG. 10 illustrates the elements ofFIG. 9 secured in the distal portion of the smooth catheter tube 20 bythe radiopaque marker band 30 which forces an annular portion of thesmooth catheter tube 20 into the wide annular groove 134 formed by thesupport ring 124 and the terminated loop 117 of the fluid jet emanator116. High velocity fluid jets 136 a-136 n are shown emanating proximallyfrom the plurality of jet orifices 122 a-122 n into the lumen 112 of thesmooth catheter tube 20 for subsequent creation of and culminating incross stream jets 140 a-140 n, as depicted by heavy lines, which flowfrom the outflow orifice 22 and return through the inflow orifice 24 forablative action with thrombus material and for maceration of foreignmaterial in concert with the high velocity fluid jets 136 a-136 n and orfor exhausting proximally with the flow within the distal portion of thesmooth catheter tube 20. A guidewire 141 is also shown in see-throughdepiction, including alternate guidewire end positions 141 a and 141 bdesignated by dashed lines, where the guidewire 141 extends along thelumen 112 of the smooth catheter tube 20, through the center void 126 ofthe terminated loop 117, and through the central passageway 128 of thesupport ring 124 into the proximal portion of the flexible tapered tip26. Guidewire 141 can be advanced beyond the flexible tapered tip 26 ofthe smooth catheter tube 20 such as during positioning of the catheterwithin the blood vessel or other body cavity, and then withdrawn toalternate guidewire end positions 141 a and 141 b, or other positionswithin the smooth catheter tube 20, or withdrawn completely from thesmooth catheter tube 20. An advantage of the present invention is thatthe guidewire 141 can be introduced by a front loading approach or by abackloading approach and, therefore, can be removed and reintroduced orcan be replaced by a different guidewire.

FIG. 11 is a side view of the distal region of the enhanced cross streammechanical thrombectomy catheter with backloading manifold 10 showing inparticular the distal end of the smooth catheter tube assembly 19positioned in a blood vessel 142 (shown in cross section) at a site of athrombotic deposit or lesion 144. While FIG. 11 depicts the smoothcatheter tube assembly 19 as being in a blood vessel in particular, itis to be understood that it is not limited to use in a blood vessel buthas utility with respect to any body cavity in general. High velocityfluid jets 136 a-136 n (shown in FIG. 10) of saline or other suitablesolution are emanated or emitted in a proximal direction from the fluidjet emanator 116 into the smooth catheter tube 20 and pass through theoutflow orifice 22 creating cross stream jets 140 a-140 n directedtoward the wall of the blood vessel 142 having thrombotic deposits orlesions 144 and thence are influenced by the low pressure at the infloworifice 24 to cause the cross stream jets 140 a-140 n to be directeddistally substantially parallel to the central axis of the blood vessel142 to impinge and break up thrombotic deposits or lesions 144 and to,by entrainment, urge and carry along the dislodged and ablatedthrombotic particulates 146 of the thrombotic deposits or lesions 144through the inflow orifice 24, a relatively low pressure region, andinto the lumen 112, which functions as a recycling maceration lumen orchamber and also as an exhaust lumen. The entrainment through the infloworifice 24 is based on entrainment by the high velocity fluid jets 136a-136 n. The outflow is driven by internal pressure which is created bythe high velocity fluid jets 136 a-136 n and the fluid entrained throughthe inflow orifice 24. The enhanced clot removal is enabled because ofthe recirculation pattern established between inflow and outfloworifices 22 and 24, which creates a flow field that maximizes drag forceon wall-adhered thrombus, and because of impingement of the cross streamjets 140 a-140 n. The cross stream jets 140 a-140 n, whilst beingforcefully directed outwardly and toward the wall of the blood vessel142, by opposite reaction urge the distal portion of the smooth cathetertube 20 in the direction opposite the outward flow direction and awayfrom the impingement area of the cross stream jets 140 a-140 n with theimmediate thrombotic deposit or lesion 144 and/or the wall of the bloodvessel 142, thus distancing the highly concentrated high velocity crossstream jets 140 a-140 n from the immediate thrombotic deposit or lesion144 and/or the wall of the blood vessel 142 and thereby minimizingpotential blood vessel wall damage. The cross stream jets 140 a-140 ntraversing between the outflow orifice 22 and the inflow orifice 24combine to offer an enhanced broad cross section ablation area, sucharea having a breadth substantially larger and having more concentratedforce than prior art devices using multiple inflow and outflow orificeswhere cross streams are of diminished force and breadth. Having aconcentrated flow combining cross stream jets 140 a-140 n offersselective and directed ablation to take place. Prior art devices usingmultiple inflow and outflow orifices and having multiple flow areasgenerate cross streams which are equally weak in all directions, as theflow force is divided between the multiple flow streams, wherebyablation forces cannot be concentrated where desired. The distal end ofthe smooth catheter tube 20 can be rotated axially to direct the crossstream jets 140 a-140 n about a longitudinal axis to have 360.degree.coverage or can be rotated axially to offer coverage partially about thelongitudinal axis, as required.

The placement of the guidewire 141 within or the removal of theguidewire 141 from the enhanced cross stream mechanical thrombectomycatheter with backloading manifold 10 influences the operation of theinvention. Suitably strong and well directed ablation flow can takeplace with a guidewire 141 extending the full length of the enhancedcross stream mechanical thrombectomy catheter with backloading manifold10 and/or additionally extending in a distal direction beyond theflexible tapered tip 26 and along the vasculature. Such ablation flowcan be further improved, enhanced, modified or otherwise influenced byvarying the location of or by full removal of the guidewire 141. Withreference to FIG. 10, the guidewire 141, as shown, allows suitabletransition of the high velocity fluid jets 136 a-136 n through theoutflow orifice 22 to form cross stream jets 140 a-140 n which returnvia the inflow orifice 24. If, for example, the guidewire 141 is urgedproximally to a guidewire end position 141 a between the inflow orifice24 and the outflow orifice 22, the inflow orifice 24 is totallyunrestricted and has less flow resistance, thereby allowing greater andmore forceful ingress of the cross stream jets 140 a-140 n laden withablated thrombotic particulates 146, whereas the flow through theoutflow orifice 22 remains substantially constant. Urging the guidewire141 further in a proximal direction to a guidewire end position 141 bdistal to the outflow orifice 22 causes the outflow orifice 22 and theinflow orifice 24 both to be totally unrestricted and both to have lessflow resistance, thereby allowing greater and more forceful flow fromthe outflow orifice 22, as well as resultantly increased ingress of thecross stream jets 140 a-140 n laden with ablated thrombotic particulates146 through the inflow orifice 24. Each of the examples given abovewhere the guidewire 141 is not totally removed from the smooth cathetertube 20 or other proximally located regions promotes sustainedmaceration of the loitering entrained ablated thrombotic particulates146 where the smaller ablated thrombotic particulates 146 are exhaustedproximally through the smooth catheter tube 20, the braided cathetertube 18, and the associated and pertinent structure proximal thereto. Inanother example, urging of the guidewire 141 to a position proximal ofthe proximal end of the braided catheter tube 18 or total removal of theguidewire 141, in addition to allowing total unrestricted flow throughthe outflow orifice 22 and the inflow orifice 24, allows unrestrictedflow of ablated thrombotic particulates 146 along the smooth cathetertube 20, the braided catheter tube 18, and the associated and pertinentstructure proximal thereto.

The preferred embodiment comprises a single outflow orifice 22, acorresponding cross stream jet which may be split in two by passagearound high pressure tube 71, and a single inflow orifice 24.

Although the preferred embodiment as illustrated incorporates an infloworifice 24 and an outflow orifice 22 aligned to the high pressure tube71, one or both of the inflow or outflow orifices may be located so thatthey do not align with the high pressure tube; in this case, other meansfor guiding a guidewire past the orifice(s) is provided to prevent theguidewire from inadvertently passing through the non-aligned orifice(s).

The invention also includes methods of treating a body vessel accordingto the aforementioned mode of operation.

FIG. 12 is a side view in cross section illustrating the introduction ofthe guidewire 141 into the enhanced cross stream mechanical thrombectomycatheter with backloading manifold 10. When it is desired to remove aguidewire, such as guidewire 141, or exchange guidewires havingdifferent attributes, backloading is facilitated by the structure of theinsert 50. Loading can be accomplished, if necessary, using theintroducer 15 to gain entry through the self-sealing hemostatic valve 88where the introducer parts the sealing structure of the self-sealinghemostatic valve 88 to allow entry of the guidewire 141 therethrough.Otherwise the guidewire can pass unaided through the self-sealinghemostatic valve 88. The tip of the guidewire may not be in properalignment with the central passageway 80, such as is shown by theguidewire 141 shown in dashed lines. In such case, impingement of thetip of the distally urged guidewire 141 with the conically-shapedbeveled surface entrance 86 of central passageway 80 directs the tip ofthe guidewire 141 to align with and to be engaged within the centralpassageway 80 of the insert 50 and to be in alignment, as shown, withinthe central passageway 80 so as to align with and be subsequentlyengaged within the proximal portion of the braided catheter tube 18 forpassage therethrough. Distal urging of the guidewire 141 also positionsthe tip of the guidewire 141 for passage through the distal region ofthe smooth catheter tube 20 where the geometry helpfully accommodatessuch passage by and along the outflow orifice 22 and the inflow orifice24 and through the fluid jet emanator 116, the support ring 124, and theflexible tapered tip 26. Preferably, the tip of the guidewire 141 isdome-shaped. Such a dome shape is easily guided by and accommodated bythe proximally-facing rounded surface of the terminated loop 117 of thefluid jet emanator 116. Use of the introducer 15 can also be utilized iffront loading of a guidewire is required for passage through theself-sealing hemostatic valve 88. Preferably, the guidewire 141 exhibitssufficient size, flexibility and other attributes to navigate thetortuous vascular paths, but exhibits sufficient rigidity not to kink,bend or otherwise be permanently deformed and to stay within theappropriate confines of the distal portion of the smooth catheter tube20 and not stray through the outflow orifice 22 or the inflow orifice24. The cross sections of the outflow orifice 22 and the inflow orifice24 are such that entry thereinto of the horizontally aligned guidewireof sufficient size and larger cross section profile is next toimpossible. Notwithstanding, the use of one pair of inflow and outfloworifices further reduces the chance of inadvertent exiting of theguidewire tip through an orifice.

The present invention also includes methods of fabricating an enhancedcross stream mechanical thrombectomy catheter with backloading manifoldincluding steps of providing components as disclosed herein and steps ofaligning the provided components and steps of affixing the alignedprovided components to retain the components in the alignedconfiguration as indicated in FIGS. 5, 7 and 10.

FIG. 13, a first alternative embodiment, is an isometric view of anenhanced cross stream mechanical thrombectomy catheter with backloadingmanifold 210, incorporating much of the structure previously described,but differing in the substitution of a smooth catheter tube assembly 212and other components and structure housed in the smooth catheter tubeassembly 212 for the smooth catheter tube assembly 19 and previouslydescribed components and structure housed in the smooth catheter tubeassembly 19. Also, previously described components are utilizedincluding the components of or components attached to or associated withthe centrally located backloading manifold 12 involving the hemostaticnut 14, the introducer 15, the flexible and tapered strain relief 16,and the braided catheter tube 18. The smooth catheter tube assembly 212of multiple layer plastic composition is connected to and extendsdistally from the braided catheter tube 18 at a junction 118 a andincludes an outflow orifice 214, an inflow orifice 216, and additionallyan evacuation orifice 218, each located in longitudinal alignment alongan imaginary line at the distal portion of the smooth catheter tubeassembly 212 near a flexible tapered tip 220 located distally at the endof the smooth catheter tube assembly 212 and each extending through thewall of the smooth catheter tube 224. For illustration purposes, theoutflow orifice 214, the inflow orifice 216, and the evacuation orifice218 are shown on the side of the smooth catheter tube assembly 212, butthey can be located along any imaginary line extending longitudinallyalong a distal surface of the smooth catheter tube assembly 212, such asis shown in FIGS. 15 and 18.

FIG. 14 is a partially exploded isometric view of the enhanced crossstream mechanical thrombectomy catheter with backloading manifold 210;FIG. 15 is a cross section side view of the components of the distalregion of the smooth catheter tube assembly 212 along line 15-15 of FIG.13; and FIG. 16 is a magnified cross section view along line 16-16 ofFIG. 15. With reference to FIGS. 14, 15 and 16, the first alternativeembodiment is now further described.

The smooth catheter tube assembly 212, the components of which aredepicted fully in FIGS. 13 and 14, includes a centrally located smoothcatheter tube 224, having lumens 222 a and 222 b, about which or inwhich other components are located, including a guidewire tube 228having a lumen 230 which aligns preferably in opposition to the outfloworifice 214, the inflow orifice 216, and the evacuation orifice 218along the opposing outer surface of the smooth catheter tube 224 andwhich extends along the smooth catheter tube 224 from and including theflexible tapered tip 220 to enter and pass within the lumen 110 of thebraided catheter tube 18 at or near the junction 118 a to the interiorof the backloading manifold 12. A flexible plastic sheath 232, part ofthe smooth catheter tube assembly 212, encompasses the smooth cathetertube 224 and extends the length thereof from the flexible tapered tip220 until reaching the junction 118 a. The proximal portion of the highpressure tube 71 extends distally and through the lumen 110 of thebraided catheter tube 18, and thence along the lumen 222 a of and alongthe smooth catheter tube 224 to terminate as part of the fluid jetemanator 116 shown in FIG. 15 adjacent to the flexible tapered tip 220at the distal end of the lumen 222 b of the smooth catheter tubeassembly 212. A deflector 234 in the form of a truncated solid structureand including a deflector face 236 suitably angled with respect to thelongitudinal axis of the smooth catheter tube 224 is located between thelumens 222 a and 222 b of the smooth catheter tube 224 and defines theseparation of the lumens 222 a and 222 b where lumen 222 a extendsproximally along the interior of the smooth catheter tube 224 from thedeflector 234 in communication with the evacuation orifice 218 and wherethe lumen 222 b extends distally from the deflector 234 in communicationwith the outflow orifice 214 and the inflow orifice 216 untilterminating at the flexible tapered tip 220. The deflector 234 islocated in close proximity to the outflow orifice 214 and is oriented tocause the deflection of the highly pressurized fluid jets projectedproximally from the fluid jet emanator 116 to be reflectingly anddeflectingly directed through the outflow orifice 214, as describedlater in detail. The deflector 234 aids in structural integrity of thedistal portion of the smooth catheter tube 224 as does the structure ofthe fluid jet emanator 116. Also shown in FIG. 14 is the junction 118 abetween the smooth catheter tube assembly 212 and the braided cathetertube 18, such junction being suitably effected to provide for a smoothand continuous coupling of the smooth catheter tube assembly 212 and thebraided catheter tube 18.

FIG. 17 is a cross section view of the smooth catheter tube assembly 212along line 17-17 of FIG. 16. Shown in particular is an elongated slot238 extending longitudinally through the upper surface of the deflector234 through which the high pressure tube 71 passes and secures such asby welding or other suitable means. Also shown is the sheath 232surroundingly encompassing the smooth catheter tube 224 and theguidewire tube 228, thereby securing the guidewire tube 228 to thesmooth catheter tube 224.

Mode of Operation

The mode of operation of the enhanced cross stream mechanicalthrombectomy catheter with backloading manifold 210 is explained withreference to FIGS. 18 and 19. FIG. 18 illustrates the distal portion ofthe smooth catheter tube assembly 212 in cross section and the use of avacuum source, such as a vacuum pump or roller pump 239, which connectsthrough the lumen 222 a of the smooth catheter tube 224 to the exhaustbranch 36 of the backloading manifold 12. High velocity fluid jets 240a-240 n are shown emanating proximally from the plurality of jetorifices 122 a-122 n of the terminated loop 117 of the fluid jetemanator 116 into the lumen 222 b of the smooth catheter tube 224 forsubsequent creation of and culminating in cross stream jets 242 a-242 n,shown by heavy lines, where the high velocity fluid jets 240 a-240 n areconcentratingly deflected and redirected by the deflector face 236 ofthe deflector 234 to flow as cross stream jets 242 a-242 n from theoutflow orifice 214 and return through the inflow orifice 216 whileaccomplishing ablative action with adhered blood vessel thrombus foreignmaterial and for maceration of foreign material in concert with the highvelocity fluid jets 240 a-240 n. A great preponderance of foreignmaterial is introduced through the inflow orifice 216 and into the lumen222 b after dislodging from a blood vessel wall for maceratingimpingement by the high velocity fluid jets 240 a-240 n. Macerated smallmass foreign material, i.e., thrombotic particulate, contained in thecross stream jets 242 a-242 n, especially that foreign material near theoutflow orifice 214, is drawn from the flow of the cross stream jets 242a-242 n by the relatively low pressure area presented at the evacuationorifice 218 along an additional and proximally directed flow 244 fromthe outflow orifice 214 to the evacuation orifice 218 and thenceproximally through and within the lumen 222 a of the smooth cathetertube 224, as also depicted by heavy lines. A previously placed guidewire(not shown) is incorporated to load the enhanced cross stream mechanicalthrombectomy catheter with backloading manifold 210 within thevasculature by first utilizing the distal end of the lumen 230 of theguidewire tube 228 followed by subsequent advancement by the enhancedcross stream mechanical thrombectomy catheter with backloading manifold210 along the guidewire in close proximity to a thrombus site. In thealternative, the first guidewire can be withdrawn completely from theenhanced cross stream mechanical thrombectomy catheter with backloadingmanifold 210 and swapped by backloading with another guidewire of otherproperties and attributes if required. An advantage of the presentinvention is that the guidewire can be introduced by a front loadingapproach or by a backloading approach and, therefore, the guidewire canbe removed and reintroduced or can be replaced by a different guidewire.

FIG. 19 is a side view of the distal region of the enhanced cross streammechanical thrombectomy catheter with backloading manifold 210 showingin particular the distal end of the smooth catheter tube assembly 212positioned in a blood vessel 142 (shown in cross section) at a site of athrombotic deposit or lesion 144. While FIG. 19 depicts the smoothcatheter tube assembly 212 as being in a blood vessel in particular, itis to be understood that it is not limited to use in a blood vessel, buthas utility with respect to any body cavity in general. High velocityfluid jets 240 a-240 n (shown in FIG. 18) of saline or other suitablesolution are emanated or emitted in a proximal direction from the fluidjet emanator 116 into the smooth catheter tube 224 and pass through theoutflow orifice 214 creating cross stream jets 242 a-242 n directedtoward the wall of the blood vessel 142 having thrombotic deposits orlesions 144 and thence are influenced by the low pressure at the infloworifice 216 to cause the cross stream jets 242 a-242 n to be directeddistally substantially parallel to the central axis of the blood vessel142 to impinge and break up thrombotic deposits or lesions 144 and to,by entrainment, urge and carry along the dislodged and ablatedthrombotic particulate 146 of the thrombotic deposits or lesions 144through the inflow orifice 216, a relatively low pressure region, andinto the lumen 222 b, which functions as a recycling maceration lumen orchamber or some thrombotic particulate 146 may enter the evacuationorifice 218. The entrainment through the inflow orifice 216 isfacilitated by a low pressure source presented by the high velocityfluid jets 240 a-240 n. The outflow is driven in part by internalpressure which is created by the high velocity fluid jets 240 a-240 n,but more generally, outflow drive is caused by the suction (low pressureregion) at the evacuation orifice 218 and proximally along lumen 222 aas provided by the vacuum pump or roller pump 239. The enhanced clotremoval is enabled by of the recirculation pattern established betweeninflow and outflow orifices 216 and 214, which creates a flow field thatmaximizes drag force on wall-adhered thrombus, and because ofimpingement of the cross stream jets 242 a-242 n. The cross stream jets242 a-242 n, while being forcefully directed outwardly and toward thewall of the blood vessel 142 by opposite reaction, urge the distalportion of the smooth catheter tube 224 in the direction opposite theoutward flow direction and away from the impingement area of the crossstream jets 242 a-242 n with the immediate thrombotic deposit or lesion144 and/or the wall of the blood vessel 142, thus distancing the highlyconcentrated cross stream jets 242 a-242 n from the immediate thromboticdeposit or lesion 144 and/or the wall of the blood vessel 142, andthereby minimizing potential blood vessel-wall damage. Such distancingalso removes the inflow orifice 216 from close proximity with and awayfrom the opposed wall of the blood vessel 142, thereby minimizing thechance of ingestion of the blood vessel 142 wall structure by the infloworifice 216.

The cross stream jets 242 a-242 n traversing between the outflow orifice214 and the inflow orifice 216 combine to offer an enhanced broad crosssection ablation area, such area having a breadth substantially largerand having more concentrated force than prior art devices using multipleinflow and outflow orifices where cross streams are of diminished forceand breadth. Having a concentrated flow combining cross stream jets 242a-242 n offers selective and directed ablation to take place. Prior artdevices using multiple inflow and outflow orifices and having multipleflow areas generate cross streams which are equally weak in alldirections, as the flow force is divided between the multiple flowstreams, whereby ablation forces cannot be concentrated where desired.The distal end of the smooth catheter tube 224 can be rotated axially todirect the cross stream jets 242 a-242 n about a longitudinal axis tohave 360.degree. coverage or can be rotated axially to offer coveragepartially about the longitudinal axis or can be operated to and fro, asrequired.

FIG. 20, a second alternative embodiment, is an isometric view of anenhanced cross stream mechanical thrombectomy catheter with backloadingmanifold 310 incorporating much of the structure previously described,especially that of the first alternative embodiment, but differing fromthe preferred embodiment, as does the first alternative embodiment, bythe substitution of, for example, a smooth catheter tube assembly 312and other components and structure housed in the smooth catheter tubeassembly 312 for the smooth catheter tube assembly 212, and previouslydescribed components and structure housed in the smooth catheter tubeassembly 212. Also, previously described components are utilizedincluding the components of or components attached to or associated withthe centrally located backloading manifold 12 involving the hemostaticnut 14, the introducer 15, the flexible and tapered strain relief 16,and the braided catheter tube 18. In the second alternative embodiment,the smooth catheter tube assembly 312 of multiple layer plasticcomposition is connected to and extends distally from the braidedcatheter tube 18 at a junction 118 b and includes an outflow orifice314, an inflow orifice 316, and an evacuation orifice 318, each locatedin longitudinal alignment along an imaginary line at the distal portionof the smooth catheter tube assembly 312 near a flexible tapered tip 320located distally at the end of the smooth catheter tube assembly 312.For illustration purposes, the outflow orifice 314, the inflow orifice316, and the evacuation orifice 318 which extend through the wall of thesmooth catheter tube 324 are shown on the side of the smooth cathetertube assembly 312, but they can be located along any imaginary lineextending longitudinally along a distal surface of the smooth cathetertube assembly 312, such as is shown in FIGS. 22 and 25.

FIG. 21 is a partially exploded isometric view of the enhanced crossstream mechanical thrombectomy catheter with backloading manifold 310;FIG. 22 is a cross section side view of the components of the distalregion of the smooth catheter tube assembly 312 along line 22-22 of FIG.20; and FIG. 23 is a magnified cross section view along line 23-23 ofFIG. 22. With reference to FIGS. 21, 22 and 23, the second alternateembodiment is now further described.

The smooth catheter tube assembly 312, the components of which aredepicted fully in FIGS. 20 and 21, includes a centrally located smoothcatheter tube 324 having lumens 322 a and 322 b, about which or in whichother components are located, including a guidewire tube 328 having alumen 330 which aligns preferably in opposition to the outflow orifice314, the inflow orifice 316, and the evacuation orifice 318 along theopposing outer surface of the smooth catheter tube 324 and which extendsalong the smooth catheter tube 324 from and including the flexibletapered tip 320 to enter and pass within the lumen 110 of the braidedcatheter tube 18 at or near the junction 118 b to the interior of thebackloading manifold 12. A flexible plastic sheath 332, part of thesmooth catheter tube assembly 312, encompasses the smooth catheter tube324 and extends the length thereof from the flexible tapered tip 320until reaching the junction 118 b. The proximal portion of the highpressure tube 71 extends distally and through the lumen 110 of thebraided catheter tube 18, and thence along the lumen 322 a of and alongthe smooth catheter tube 324 to terminate as part of a multidirectionalfluid jet emanator 116 a shown in FIG. 22. In this embodiment, themultidirectional fluid jet emanator 116 a is located between the infloworifice 316 and the evacuation orifice 318 of the smooth catheter tube324 and defines the separation of the lumens 322 a and 322 b where lumen322 a extends proximally along the interior of the smooth catheter tube324 from the multidirectional fluid jet emanator 116 a in communicationwith the evacuation orifice 318 and where the lumen 322 b extendsdistally from the multidirectional fluid jet emanator 116 a incommunication with the inflow orifice 316 and the outflow orifice 314until terminating at a deflector 334 adjacent to the flexible taperedtip 320. The deflector 334, in the form of a truncated solid structureand including a deflector face 336 suitably angled with respect to thelongitudinal axis of the smooth catheter tube 324, is located at thedistal end of the lumen 322 b in close proximity and slightly distal ofthe outflow orifice 314 and is oriented to cause the deflection of thehigh velocity fluid jets projected distally from the multidirectionalfluid jet emanator 116 a to be reflectingly and deflectingly directedthrough the outflow orifice 314, as described later in detail. Thedeflector 334 aids in structural integrity of the distal portion of thesmooth catheter tube 324 as does the structure of the multidirectionalfluid jet emanator 116 a. Also shown in FIG. 21 is the junction 118 bbetween the smooth catheter tube assembly 312 and the braided cathetertube 18, such junction being suitably effected to provide for a smoothand continuous coupling of the smooth catheter tube assembly 312 and thebraided catheter tube 18. FIG. 23 best illustrates the multidirectionalfluid jet emanator 116 a which is a variation of the previouslydescribed fluid jet emanator 116. The multidirectional fluid jetemanator 116 a includes features found in the fluid jet emanator 116,but the terminated loop 117 of the fluid jet emanator 116 is replaced bya proximal loop 117 a, and a connected distal loop 117 b is added. Boththe proximal loop 117 a and the distal loop 117 b are in communicationwith each other and with the high pressure tube 71 and they are locatedon opposing ends of a support ring 124 a. A plurality of proximallydirected jet orifices 123 a-123 n are located on the proximal side ofthe proximal loop 117 a, and a plurality of distally directed jetorifices 125 a-125 n are located on the distal side of the distal loop117 b for simultaneous emanation of high velocity fluid jets in oppositedirections. The multidirectional fluid jet emanator 116 a is suitablyaffixed within the smooth catheter tube 324 between the inflow orifice316 and the evacuation orifice 318.

FIG. 24 is a cross section view of the smooth catheter tube assembly 312along line 24-24 of FIG. 23. Shown in particular is the evacuationorifice 318 which passes through both the plastic sheath 332 and thesmooth catheter tube 324.

Mode of Operation

The mode of operation of the enhanced cross stream mechanicalthrombectomy catheter with backloading manifold 310 is explained withreference to FIGS. 25 and 26. FIG. 25 illustrates the distal portion ofthe smooth catheter tube assembly 312 in cross section and the use of anoptional vacuum source, such as a vacuum pump or roller pump 339, whichconnects through the lumen 322 a of the smooth catheter tube 324 to theexhaust branch 36 of the backloading manifold 12. High velocity fluidjets 340 a-340 n are shown emanating distally from the plurality of jetorifices 125 a-125 n in the distal loop 117 b of the fluid jet emanator116 into the lumen 322 b of the smooth catheter tube 324 for subsequentcreation of and culminating in cross stream jets 342 a-342 n, as shownby heavy lines, where the high velocity fluid jets 340 a-340 n areconcentratingly deflected and redirected by the deflector face 336 ofthe deflector 334 to flow as cross stream jets 342 a-342 n from theoutflow orifice 314 and return through the inflow orifice 316 whileaccomplishing ablative action with adhered blood vessel thrombus foreignmaterial and for maceration of foreign material in concert with the highvelocity fluid jets 340 a-340 n. A great preponderance of foreignmaterial is introduced through the inflow orifice 316 and into the lumen322 b after dislodging from a blood vessel wall for maceratingimpingement by the high velocity fluid jets 340 a-340 n. Macerated smallmass foreign material, i.e., thrombotic particulate, contained in thecross stream jets 342 a-342 n, especially that foreign material near theinflow orifice 316, is drawn from the flow of the cross stream jets 342a-342 n by the relatively low pressure area presented at the evacuationorifice 318 along an additional and proximally directed flow 344 fromnear the inflow orifice 316 to the evacuation orifice 318 and thenceproximally through and within the lumen 322 a of the smooth cathetertube 324, as also depicted by heavy lines. Proximally directed highvelocity fluid jets 346 a-346 n emanating proximally from the pluralityof jet orifices 123 a-123 n in the proximal loop 117 a into the lumen322 a of the smooth catheter tube 324 create the relatively low pressurepresented at the evacuation orifice 318 to draw thrombotic particulatethrough the evacuation orifice 318 and to provide a proximally directeddriving force to urge the thrombotic particulate proximally along thelumen 322 a.

A previously placed guidewire (not shown) is incorporated to load theenhanced cross stream mechanical thrombectomy catheter with backloadingmanifold 310 within the vasculature by first utilizing the distal end ofthe lumen 330 of the guidewire tube 328 followed by subsequentadvancement by the enhanced cross stream mechanical thrombectomycatheter with backloading manifold 310 along the guidewire in closeproximity to a thrombus site. In the alternative, the first guidewirecan be withdrawn completely from the enhanced cross stream mechanicalthrombectomy catheter with backloading manifold 310 and swapped bybackloading with another guidewire of other properties and attributes,if required. An advantage of the present invention is that the guidewirecan be introduced by a front loading approach or by a backloadingapproach and, therefore, the guidewire can be removed and reintroducedor can be replaced by a different guidewire.

FIG. 26 is a side view of the distal region of the enhanced cross streammechanical thrombectomy catheter with backloading manifold 310 showingin particular the distal end of the smooth catheter tube assembly 312positioned in a blood vessel 142 (shown in cross section) at a site of athrombotic deposit or lesion 144. While FIG. 26 depicts the smoothcatheter tube assembly 312 as being in a blood vessel in particular, itis to be understood that it is not limited to use in a blood vessel buthas utility with respect to any body cavity in general. High velocityfluid jets 340 a-340 n (shown in FIG. 25) of saline or other suitablesolution are emanated or emitted in a distal direction from themultidirectional fluid jet emanator 116 a into the lumen 322 b of thesmooth catheter tube 324 and are concentratingly deflected andredirected by the deflector 334 to pass through the outflow orifice 314creating cross stream jets 342 a-342 n directed toward the wall of theblood vessel 142 having thrombotic deposits or lesions 144 and thenceare influenced by the low pressure at the inflow orifice 316 to causethe cross stream jets 342 a-342 n to be directed proximallysubstantially parallel to the central axis of the blood vessel 142 toimpinge and break up thrombotic deposits or lesions 144 and to, byentrainment, urge and carry along the dislodged and ablated thromboticparticulate 146 of the thrombotic deposits or lesions 144 through theinflow orifice 316, a relatively low pressure region, and into the lumen322 b, which functions as a recycling maceration lumen or chamber, orsome thrombotic particulate 146 may enter the evacuation orifice 318.The entrainment through the evacuation orifice 318 is facilitated by alow pressure source presented by the high velocity fluid jets 346 a-346n directed proximally along the lumen 322 a for entrainment ofthrombotic particulate 146 along the path of the proximally directedflow 344 for ingestion of thrombotic particulate 146 through theevacuation orifice 318. The outflow is driven by internal pressure whichis created by the high velocity fluid jets 346 a-346 n proximallydirected along the lumen 322 a, but alternatively, the outflow drive canbe assisted by the suction (low pressure region) at the lumen 322 a asprovided by the vacuum pump or roller pump 339. The enhanced clotremoval is enabled by the recirculation pattern established betweeninflow and outflow orifices 316 and 314, which creates a flow field thatmaximizes drag force on wall-adhered thrombus, and because ofimpingement of the cross stream jets 342 a-342 n. The cross stream jets342 a-342 n, while being forcefully directed outwardly and toward thewall of the blood vessel 142 by opposite reaction, urge the distalportion of the smooth catheter tube 324 in the direction opposite theoutward flow direction and away from the impingement area of the crossstream jets 342 a-342 n with the immediate thrombotic deposit or lesion144 and/or the wall of the blood vessel 142, thus distancing the highlyconcentrated cross stream jets 342 a-342 n from the immediate thromboticdeposit or lesion 144 and/or the wall of the blood vessel 142, andthereby minimizing potential blood vessel wall damage. Such distancingalso removes the inflow orifice 316 from close proximity with and awayfrom the opposed wall of the blood vessel 142, thereby minimizing thechance of ingestion of the blood vessel 142 wall structure by the infloworifice 316.

The cross stream jets 342 a-342 n traversing between the outflow orifice314 and the inflow orifice 316 combine to offer an enhanced broad crosssection ablation area, such area having a breadth substantially largerand having more concentrated force than prior art devices using multipleinflow and outflow orifices where cross streams are of diminished forceand breadth. Having a concentrated flow combining cross stream jets 342a-342 n offers selective and directed ablation to take place. Prior artdevices using multiple inflow and outflow orifices and having multipleflow areas generate cross streams which are equally weak in alldirections, as the flow force is divided between the multiple flowstreams, whereby ablation forces cannot be concentrated where desired.The distal end of the smooth catheter tube 324 can be rotated axially todirect the cross stream jets 342 a-342 n about a longitudinal axis tohave 360.degree. coverage or can be rotated axially to offer coveragepartially about the longitudinal axis or can be operated to and fro, asrequired.

FIG. 27, a third alternative embodiment, is an isometric view of anenhanced cross stream mechanical thrombectomy catheter with backloadingmanifold 410 incorporating much of the structure previously described,but differing by the substitution of a smooth catheter tube assembly412, including a smooth catheter tube 424, which is curved approximately180.degree., and other components and structure housed in the smoothcatheter tube assembly 412 for the straight smooth catheter tubeassembly 19 and previously described components and structure housed inthe straight smooth catheter tube assembly 19 of the first embodiment.Also, previously described components are utilized including thecomponents of or components attached to or associated with the centrallylocated backloading manifold 12 involving the hemostatic nut 14, theintroducer 15, the flexible and tapered strain relief 16, and thebraided catheter tube 18. The smooth catheter tube 424, which iscontinuous, flexible and exhibits position memory, includes a curvedsection 424 a located between a reversed section 424 b and a straightsection 424 c opposing the reversed section 424 b. The smooth cathetertube assembly 412 is connected to and extends distally from the braidedcatheter tube 18 at a junction 118 c and includes an outflow orifice 414and an inflow orifice 416 each extending through the wall of thereversed section 424 b of the smooth catheter tube 424 and each locatedin longitudinal alignment along an imaginary line at the inwardly facingaspect 418 of the reversed section 424 b of the smooth catheter tube 424and each opposingly facing the straight section 424 c of the smoothcatheter tube 424. Also included as part of the reversed section 424 bis a distally located flexible tapered tip 420. Radiopaque marker bands419 and 421 are located on the reversed section 424 b of the smoothcatheter tube 424 flanking the outflow orifice 414 and the infloworifice 416.

FIG. 28 is a partially exploded isometric view of the enhanced crossstream mechanical thrombectomy catheter with backloading manifold 410;and FIG. 29 is a cross section side view of the components of the distalregion of the smooth catheter tube assembly 412 along line 29-29 of FIG.27. With reference to FIGS. 28 and 29, the third alternative embodimentis now further described.

The smooth catheter tube assembly 412, the components of which aredepicted fully in FIGS. 27 and 28, includes a lumen 422 extending thelength of the centrally located smooth catheter tube 424 including theflexible tapered tip 420, the reversed section 424 b, the curved section424 a, and the straight section 424 c about which and in which othercomponents are located to connect with the lumen 110 of the braidedcatheter tube 18 at or near the junction 118 c to the interior of thebackloading manifold 12. The proximal portion of the high pressure tube71 extends distally and through the lumen 110 of the braided cathetertube 18, and thence along the lumen 422 of and along the smooth cathetertube 424 to terminate as part of the fluid jet emanator 116, shown inFIG. 29, adjacent to the flexible tapered tip 420 at the distal end ofthe lumen 422 of the smooth catheter tube 424. In addition to theinwardly facing aspect 418 along the reversed section 424 b, outwardlyfacing aspects are incorporated into the smooth catheter tube 424,including an outwardly facing aspect 426 along the outer portion of thereversed section 424 b and an outwardly facing aspect 428 along theouter portion of the straight section 424 c. Also shown in FIG. 27 isthe junction 118 c between the smooth catheter tube assembly 412 and thebraided catheter tube 18, such junction being suitably effected toprovide for a smooth and continuous coupling of the smooth catheter tubeassembly 412 and the braided catheter tube 18.

Mode of Operation

The mode of operation of the enhanced cross stream mechanicalthrombectomy catheter with backloading manifold 410 is explained withreference to FIGS. 29, 30 and 31. High velocity fluid jets 440 a-440 nare shown emanating proximally from the plurality of jet orifices 122a-122 n of the terminated loop 117 into the lumen 422 of the smoothcatheter tube 424 for subsequent creation of and culminating in crossstream jets 442 a-442 n, shown by heavy lines, where the high velocityfluid jets 440 a-440 n flow as cross stream jets 442 a-442 n from theoutflow orifice 414 and return through the inflow orifice 416, whileaccomplishing ablative action with adhered blood vessel thrombusmaterial and for maceration of foreign material in concert with the highvelocity fluid jets 440 a-440 n. Foreign material is introduced throughthe inflow orifice 416 and into the lumen 422 after dislodging from avessel wall for macerating impingement by the high velocity fluid jets440 a-440 n. Macerated foreign material, i.e., thrombotic particulate,contained in the cross stream jets 442 a-442 n, flows through and withinthe lumen 422 of the smooth catheter tube 424, as also depicted by heavylines. The cross stream jets 442 a-442 n, while being forcefullydirected outwardly and toward the wall of the blood vessel 142 byopposite reaction, urge the distal portion of the smooth catheter tube424 in the direction opposite the outward flow direction and away fromthe impingement area of the cross stream jets 442 a-442 n with theimmediate thrombotic deposit or lesion 144 and/or the wall of the bloodvessel 142, thus distancing the cross stream jets 442 a-442 n from theimmediate thrombotic deposit or lesion 144 and/or the wall of the bloodvessel 142, and thereby minimizing potential blood vessel wall damage.More specifically, the reversed section 424 b can be positioned in veryclose proximity with or can intimately engage the inner wall of theblood vessel 142, as described later in detail. Such distancing alsoremoves the inflow orifice 416 from close proximity with and away fromthe opposed wall of the blood vessel 142, thereby minimizing the chanceof ingestion of the blood vessel 142 wall structure by the infloworifice 416. The cross stream jets 442 a-442 n traversing between theoutflow orifice 414 and the inflow orifice 416 combine to offer anenhanced broad cross section ablation area, such area having a breadthsubstantially larger and having more concentrated force than prior artdevices using multiple inflow and outflow orifices where cross streamsare of diminished force and breadth. Having a concentrated flowcombining cross stream jets 442 a-442 n allows selective ablation totake place.

FIG. 30 is a side view of the distal region of the enhanced cross streammechanical thrombectomy catheter with backloading manifold 410 showing,in particular, the distal end of the smooth catheter tube 424 positionedin a blood vessel 142 (shown in cross section) at a site of a thromboticdeposit or lesion 144, and FIG. 31 is a cross section view along line31-31 of FIG. 30 showing ablative action of the cross stream jets 442a-442 n with the thrombotic deposit or lesion 144, as previouslydescribed, and additionally shows abrading or scraping action of thedistal end of the smooth catheter tube 424 by intimate contact withforeign matter, such as thrombus material 144, in a blood vessel 142which could be a large blood vessel. While FIG. 30 depicts the smoothcatheter tube 424 as being in a blood vessel in particular, it is to beunderstood that it is not limited to use in a blood vessel, but hasutility with respect to any body cavity in general. High velocity fluidjets 440 a-440 n (shown in FIG. 29) of saline or other suitable solutionare emanated or emitted in a proximal direction from the fluid jetemanator 116 into the smooth catheter tube 424 and pass through theoutflow orifice 414 creating cross stream jets 442 a-442 n directedtoward the wall of the blood vessel 142 having thrombotic deposits orlesions 144, and thence are influenced by the low pressure at the infloworifice 416 to cause the cross stream jets 442 a-442 n to be directeddistally substantially parallel to the central axis of the blood vessel142 to impinge and break up thrombotic deposits or lesions 144 and to,by entrainment, urge and carry along the dislodged and ablatedthrombotic particulate 146 of the thrombotic deposits or lesions 144through the inflow orifice 416, a relatively low pressure region, andinto the lumen 422 which functions as a recycling maceration lumen orchamber. The entrainment through the inflow orifice 416 is facilitatedby a low pressure source presented by the high velocity fluid jets 440a-440 n. The outflow is driven by internal pressure which is created bythe high velocity fluid jets 440 a-440 n. The enhanced clot removal isenabled because of the recirculation pattern established between inflowand outflow orifices 416 and 414, which creates a flow field thatmaximizes drag force on wall-adhered thrombus and because of impingementof the cross stream jets 442 a-442 n.

Intimate contact of or close proximity of the generally distal portionof the smooth catheter tube 424 to the inside wall of the blood vessel142, as shown best in FIG. 31, offers yet another innovative method ofthrombotic deposit or lesion 144 removal. The cross stream jets 442a-442 n, while being forcefully directed outwardly and toward the wallof the blood vessel 142 during ablation activities by opposite reaction,urge the generally distal portion of the smooth catheter tube 424 in thedirection opposite the outward flow direction and away from theimpingement area of the cross stream jets 442 a-442 n with the immediatethrombotic deposit or lesion 144 and/or the wall of the blood vessel142, thus distancing the cross stream jets 442 a-442 n from theimmediate thrombotic deposit or lesion 144 and/or the wall of the bloodvessel 142, and thereby minimizing the danger or chance of potentialblood vessel wall damage or ingestion. Thus, the reversed section 424 b,particularly the outwardly facing aspect 426 thereof, is forciblymaneuvered into intimate contact or into close proximity to the insidewall of the blood vessel 142, as shown in FIG. 31. Such intimate contactor close proximity to the inside wall of the blood vessel 142 isutilized to advantage by rotating the enhanced cross stream mechanicalthrombectomy catheter with backloading manifold 410, particularly thesmooth catheter tube 424, within the blood vessel 142, such as indicatedby rotation arrows 444. Such causes scraping and abrading impingement ofthe reversed section 424 b, especially the outwardly facing aspect 426thereof, with the thrombotic deposit or lesion 144 at or near the innerwall of the blood vessel 142 to urge thrombotic (and lesion) particulate146 a to part from the general structure of the thrombotic deposits orlesion 144 and be entrained into the flow of the cross stream jets 442a-442 n for maceration and/or evacuation through the lumen 422, as shownin FIG. 31. To and fro operation of the enhanced cross stream mechanicalthrombectomy catheter with backloading manifold 410 can also beincorporated into operation of the enhanced cross stream mechanicalthrombectomy catheter with backloading manifold 410 either singularly orin combination with rotation, as just described. Further, if the generaldistal end of the smooth catheter tube 424 is larger, or if the bloodvessel is smaller, both the straight section 424 c with the outwardlyfacing aspect 428 and the reversed section 424 b with the outwardlyfacing aspect 426 can be utilized for rotational or for to and fromotion scraping and abrading impingement with the thrombotic deposits orlesions 144 at or near the inner wall of the blood vessel 142 to urgethrombotic (and lesion) particulate 146 a to part from the generalstructure of the thrombotic deposits or lesion 144 to be entrained intothe flow of the cross stream jets 442 a-442 n for maceration and/orevacuation through the lumen 422. Even more vigorous scraping andabrading could be accomplished if the general distal end of the smoothcatheter tube 424 were slightly oversized with respect to the bloodvessel 142.

A previously placed guidewire (not shown) is incorporated to load theenhanced cross stream mechanical thrombectomy catheter with backloadingmanifold 410 within the vasculature by first utilizing the distal end ofthe lumen 422 followed by subsequent advancement by the enhanced crossstream mechanical thrombectomy catheter with backloading manifold 410along the guidewire in close proximity to a thrombus site. In thealternative, the first guidewire can be withdrawn completely from theenhanced cross stream mechanical thrombectomy catheter with backloadingmanifold 410 and swapped by backloading with another guidewire of otherproperties and attributes, if required. An advantage of the presentinvention is that the guidewire can be introduced by a front loadingapproach or by a backloading approach and, therefore, can be removed andreintroduced or can be replaced by a different guidewire.

The concentrated cross stream jets 442 a-442 n traversing between theoutflow orifice 414 and the inflow orifice 416 combine to offer anenhanced broad cross section ablation area, such area having a breadthsubstantially larger and having more concentrated force than prior artdevices using multiple inflow and outflow orifices where cross streamsare of diminished force and breadth. Having a concentrated flowcombining cross stream jets 442 a-442 n offers selective and directedablation to take place. Prior art devices using multiple inflow andoutflow orifices and having multiple flow areas generate cross streamswhich are equally weak in all directions, as the flow force is dividedbetween the multiple flow streams, whereby ablation forces cannot beconcentrated where desired. The distal end of the smooth catheter tube424 can be rotated axially to direct the cross stream jets 442 a-442 nabout a longitudinal axis to have 360.degree. coverage or can be rotatedaxially to offer coverage partially about the longitudinal axis, asrequired.

FIG. 32, a fourth alternative embodiment, is a side view of a smoothcatheter tube 450 similar for the most part to and using componentsassociated with the smooth catheter tube 20 of the first embodiment foruse with an enhanced cross stream mechanical thrombectomy catheter withbackloading manifold. The smooth catheter tube 450 includes a flexibletapered tip 452, an inflow orifice 458, and an outflow orifice 460, eachorifice extending through the wall of the smooth catheter tube 450 wherethe outflow orifice takes on an L-shape to influence and shape thepattern of the cross stream jets which pass therethrough. The outfloworifice 460, as well as even the inflow orifice, could incorporate othershapes, such as, but not limited to, round, oval, elliptical, obround,tapered, slotted, rectangular, and rounded corner, or could beprotruding. Radiopaque marker bands 454 and 456 are provided, as in theother embodiments.

FIG. 33, a fifth alternative embodiment, is a view of the distal portionof an alternatively provided smooth catheter tube assembly 19 aincorporating the components of the smooth catheter assembly 19 shown inthe first embodiment including additional outflow orifices and infloworifices in equal and symmetric angular off-center opposition to themain outflow orifice 22 and the main inflow orifice 24.

FIGS. 34 a and 34 b are cross section views through the outflow orificesand inflow orifices of the smooth catheter tube assembly 19 a along thelines 34 a-34 a and 34 b-34 b of FIG. 33. With reference to FIGS. 33, 34a and 34 b, the additional outflow and inflow orifices are nowdescribed. The additional outflow orifices 500 and 504 and infloworifices 502 and 506, in sets, are located along imaginary linesextending longitudinally along the distal surface of the smooth cathetertube 20 and extend through the wall of the smooth catheter tube 20 wheresuch imaginary lines preferably are parallel and offset in equiangularand symmetrical fashion from direct opposition with an imaginary lineupon which the outflow orifice 22 and the inflow orifice 24 can align.Although two sets of additional outflow orifices and inflow orifices areshown, any number of sets can be incorporated as desired so long assymmetry is maintained. The sets of additional outflow orifices andinflow orifices include outflow orifices 500 and 504 and inflow orifices502 and 506 which are smaller than outflow orifice 22 and inflow orifice24 which, in total and in combination, produce additional cross streamjet flow, force and quantity less than that provided by the outfloworifice 22 and the inflow orifice 24. One additional set of outfloworifices and inflow orifices includes an outflow orifice 500 and aninflow orifice 502. Another additional set of outflow orifices andinflow orifices includes an outflow orifice 504 and an inflow orifice506.

FIG. 35 is a side view in cross section like FIG. 10 wherein the distalportion of the smooth catheter tube 20 additionally shows the outfloworifice 504 and the inflow orifice 506 in the structure thereof. Inaddition to the attributes, features and flow paths described in FIG.10, high velocity fluid jets 136 a-136 n are shown emanating proximallyfrom the plurality of jet orifices 122 a-122 n into the lumen 112 of thesmooth catheter tube 20 for subsequent creation of and culminating incross stream jets 508 a-508 n shown traveling from the outflow orifice504 and returning through the inflow orifice 506 for entry formaceration by the high velocity fluid jets 136 a-136 n and/or exhaustingproximally with the flow within the distal portion of the smoothcatheter tube 20 as generally depicted by arrowed lines. The outfloworifice 500 and the inflow orifice 502 are incorporated into use in thesame manner culminating in symmetrically disposed cross stream jets 510a-510 n traveling from the outflow orifice 500 and returning through theinflow orifice 502, as shown in FIG. 36.

In addition to longitudinal alignment of the outflow orifice 500 andcorresponding inflow orifice 502 and of the outflow orifice 504 andcorresponding inflow orifice 506 with respect to each other and to theinflow orifice 22 and the outflow orifice 24 along imaginary lines,symmetrical alignment attributes and relationships are also addressed inthe terms of cross stream jet flow region relationships as shown inFIGS. 34 a and 34 b. A major cross stream jet flow region 512 centersalong and about the cross stream jets 140 a-140 n, the outflow orifice22 and the inflow orifice 24 and substantially along the center of thelumen 112, such region being substantially perpendicular to the outfloworifice 22 and the inflow orifice 24. In a somewhat similar fashion, aminor cross stream jet flow region 514 centers along and about the crossstream jets 510 a-510 n (FIG. 36), the outflow orifice 500 and theinflow orifice 502 and substantially along the center of the lumen 112such region being substantially perpendicular to the outflow orifice 500and the inflow orifice 502. Also in a somewhat similar fashion, a minorcross stream jet flow region 516 centers along and about the crossstream jets 508 a-508 n, the outflow orifice 504 and the inflow orifice506 and substantially along the center of the lumen 112, such regionbeing substantially perpendicular to the outflow orifice 504 and theinflow orifice 506. Symmetrical angular relationships are maintainedbetween major cross stream jet flow region 512 and each of the minorcross stream jet flow regions 514 and 516. For purposes of example andillustration, an angle X between the major cross stream jet flow region512 and the minor cross stream jet flow region 514 corresponds to and isthe same value as an angle X between the major cross stream jet flowregion 512 and the minor cross stream jet flow region 516, wherebysymmetry exists. The value of the angle X can be unilaterally changedduring manufacturing to maintain symmetry, as just previously described.The resultant combination of symmetric but lesser flow along and aboutthe minor cross stream jet flow regions 514 and 516 opposes the strongerflow along and about the major cross stream jet flow region 512 toassist in centering of the smooth catheter tube assembly 19 a within ablood vessel, as well as offering ablation services while still allowingurging of the smooth catheter tube assembly 19 a toward the periphery ofa blood vessel 142.

FIG. 36 is like FIG. 11 wherein a side view of the distal region of theenhanced cross stream thrombectomy catheter with backloading manifold 10incorporating the use of the smooth catheter tube assembly 19 a is shownpositioned in a blood vessel 142 at a site of a thrombotic deposit orlesion 144 or other undesirable matter. In addition to and incooperation with the mode of operation of the first embodiment, such asdescribed with reference to FIG. 11 and associated figures, the use andfeatures of the outflow orifice 500 and the inflow orifice 502 and ofthe similarly constructed and similarly functioning outflow orifice 504and inflow orifice 506 (not shown in this FIG. 36) are described. Thecross stream jets 510 a-510 n, which are directly related to the minorcross stream jet flow region 514 and similar to cross stream jets 508a-508 n which are directly related to the minor cross stream jet flowregion 516, are directed away from the main cross stream path such asprovided by the cross stream jets 140 a-140 n which are directly relatedto the major cross stream jet flow region 512, to offer additionalablation and exhausting of thrombotic deposits or lesions 144 to thatregion where the smooth catheter tube 20 is directed and urged towardthe blood vessel 144 by the more influential power of the relativelystronger cross stream jets 140 a-140 n. Such positional urging of thesmooth catheter tube 20, as described in the first embodiment, is thedominant factor in urging of the smooth catheter tube 20 away from thewall of the blood vessel 142 near the outflow orifice 22 and the infloworifice 24, as the flow and force therethrough is greater than thatprovided by such combined flow and force through the outflow orifice 500to the inflow orifice 502 and through the outflow orifice 504 to theinflow orifice 506. The use of the outflow orifice 500 and the infloworifice 502 and of the similarly constructed and similarly functioningoutflow orifice 504 and the inflow orifice 506 provides for morecomplete ablation and exhausting while still allowing urging of thesmooth catheter tube 20 towards the side of the blood vessel 142opposite the greater ablation activity. Symmetry of the cross stream jetflows is provided by the equiangular offset of the outflow orifice 500and the inflow orifice 502 and of the similarly constructed andsimilarly functioning outflow orifice 504 and the inflow orifice 506with respect to the cross stream jet flow provided by the outfloworifice 22 and the inflow orifice 24. Such symmetry ensures stability ofthe smooth catheter tube assembly 19 a during ablation procedures.

Various modifications can be made to the present invention withoutdeparting from the apparent scope thereof.

85-106. (canceled)
 107. A thrombectomy catheter comprising: a catheterbody extending from a catheter distal portion toward a catheter proximalportion, the catheter body including a catheter lumen; a high pressuretube extending through the catheter lumen from the catheter proximalportion toward the catheter distal portion, the high pressure tube incommunication with a fluid source near the catheter proximal portion; amultidirectional fluid jet emanator in communication with the highpressure tube, the fluid jet emanator having at least one jet orificefor directing at least one first high velocity fluid jet from said fluidjet emanator in one direction and at least one jet orifice for directingat least one second high velocity fluid jet from said fluid jet emanatorin another direction; an outflow orifice configured to generate a jetstream out of the catheter body with the fluid jet, the outflow orificeis located at a discrete location along the catheter perimeter of thecatheter distal portion; an entrainment inflow orifice positioned alongthe catheter perimeter of the catheter distal portion, the entrainmentinflow orifice is configured to receive a jet stream first portion anddirect the jet stream first portion toward the outflow orifice incombination with the first high velocity fluid jet; and an exhaustinflow orifice positioned along the catheter perimeter of the catheterdistal portion, the exhaust inflow orifice is configured to receive ajet stream second portion and direct the jet stream second portion incombination with the second high velocity fluid jet toward the catheterproximal portion, wherein the exhaust inflow orifice is separate fromthe entrainment inflow orifice.
 108. The thrombectomy catheter of claim107, wherein the entrainment inflow orifice is positioned proximallyrelative to the outflow orifice, and the entrainment inflow orifice ispositioned distally relative to the exhaust inflow orifice.
 109. Thethrombectomy catheter of claim 108, wherein the fluid jet emanator ispositioned between the entrainment inflow orifice and the exhaust infloworifice.
 110. The thrombectomy catheter of claim 108, wherein the firsthigh velocity fluid jet is directed distally towards the outfloworifice.
 111. The thrombectomy catheter of claim 108, wherein the secondhigh velocity fluid jet is directed proximally towards the catheterproximal portion.
 112. The thrombectomy catheter of claim 108, whereinthe first high velocity fluid jet is directed distally towards theoutflow orifice, and wherein the second high velocity fluid jet isdirected proximally towards the catheter proximal portion.
 113. Thethrombectomy catheter of claim 107 further comprising at least onedeflector positioned within the catheter lumen adjacent to the outfloworifice, and the at least one deflector is configured to direct thefirst high velocity fluid jet toward the outflow orifice.